Iran has agreed new terms of cooperation with the UN atomic watchdog regarding the agency's investigation into Tehran's nuclear activities, a top Iranian official said here Tuesday.

But the head of Iran's Atomic Energy Organisation, Ali Akbar Salehi, declined to say what the new cooperation would entail.

A source close to the International Atomic Energy Agency told AFP that nothing substantially new had been agreed between the two sides.

"Nothing new has been agreed," the source said, speaking on condition of anonymity.

Speaking to reporters after the meeting, Salehi said: "We managed to come to an agreement to set a new framework for deeper cooperation for the future."

When pressed on what form that new cooperation would take, Salehi refused to elaborate.

"Details will be revealed at the proper time. We hope we will be witnessing in the future improved cooperation. We think the international environment is also very conducive vis-a-vis this issue," Salehi said.

The IAEA itself refused to comment on Salehi's remarks, following the talks with agency chief Mohamed ElBaradei.

A report by Iran's official IRNA news agency quoted Salehi as saying he also met newly appointed IAEA chief Yukiya Amano, whom he invited to visit Iran "at the first opportunity... so he can witness our nuclear activities close-up and Amano accepted."

"We had good negotiations... We asked (him) to look at all nations equally, meaning not to incline towards this or that nation and to follow his work independently," Salehi was quoted as saying.

Amano, of Japan, takes over as director general on December 1.

Salehi's comments came a day after Iran agreed to meet six world powers to talk next month in what could be a potential thaw in relations with the international community over the Tehran's controversial nuclear activities.

Salehi said the cooperation would not cover allegations that Iran conducted studies in the past into weaponisation, currently the main obstacle to resolving the IAEA's six-year Iranian investigation.

The watchdog insists that Tehran must respond to the allegations in order to ascertain the true nature of the activities.

But Iran has dismissed the allegations as "baseless" and "fabricated", but done nothing so far to disprove them.

"The alleged studies is from our point of view a dead issue. This is just like a movie which is very consistent and comprehensive but at the end it is a fiction," Salehi said.

The IAEA has also repeatedly demanded that Iran provide more information about its heavy water reactor at Arak and apply the so-called "additional protocol" giving the agency enhanced inspection powers.

But Salehi said Iran had already done this in the past and "been adversely rewarded".

Thus, "the ball is the court of the others, and they have to win the trust of our people and the trust of our government," he said.

Asked whether the new cooperation might also entail giving UN inspectors increased access to the reactor in Arak and the enrichment plant in Natanz, Salehi was similarly evasive.

"We have already shown our forthcoming in this regard," he said. "The new cooperation will be evolved in the future."